Ive only ever had fish that need bowls so Ive never used a filter before. I recently bought a 10 gallon (which I dont know if Ill keep becuase of problems I posted in the hardware forum) and it uses a power filter. Im curious as to how often I need to change the actual filter of my filter. It said on the packaging to do it every month but my friend says she doesnt do it that often. Do i need to buy a new cartridge every month or can I just give it a good rinse. Thanks.

I only rinse my filter pads when the flow rate is reduced. It is a good idea to rinse them in dirty tank water during a water change (separate bucket, not in the tank). Change the filter pad when it starts falling apart

Yep, it is much better to just keep rinsing the filter in used tank water. The filter holds a lot of the good bacteria that keeps the tank healthy. Like Menagerie, I only rinse my filter pads when I notice the flow rate slowing down.

If you tell us what kind of filter it is, we may have some more tips as well.